Lubricating system



IHHIII IN y W. F. STREHLOW LUBRICATING SYSTEM Original Filed June 13,

as L325: 22;

atented June 3, 1941 STATES PATENT OFFICE LUBRICATIN G SYSTEM Originalapplication June :13, 1935, Serial No.

1936. Serial No. 93,955

3 Claims.

This invention relates to lubricating systems and is concerned morespecifically with a system for lubricating driving gears for a powertakeofl shaft on a tractor. This application is a division ofapplication Serial No. 26,352, filed June 13, 1935, issued as Pat. No.2,073,613, Conrad E. Frudden and Walter F. Strehlow, Motor vehicle.

It is an object of the invention to lubricate the driving gears for apulley shaft, or other power takeoff shaft on a tractor, by transferringlubricant from the transmission housing of the tractor into a separatecompartment containing said driving gears.

Another object of the invention is to circulate through the separatecompartment containing the driving gears for the power takeoff shaft, aconstant flow of lubricant and to maintain said lubricant within thecompartment at such a level that it may not flow out at the openingthrough which the power takeoff shaft passes into the compartment.

Another object of the invention is to maintain the lubricant in thecompartment for the driving gears of the power takeofl shaft, at thementioned level irrespective of whether the transmission housing isfilled with its normal amount of lubricant or with less than its normalamount.

Another object of the invention is to provide a simple, inexpensive andeflicient lubricating system for the driving gears of a power takeoffshaft on a tractor.

These and other objects and advantages of the invention will be apparentfrom the following description. A clear conception of an embodiment ofthe invention and of the operation of a device constructed in accordancetherewith may be had by referring to the drawing accompanying andforming a part of this specification.

Fig. 1 is a vertical longitudinal sectional view of the clutch mechanismand speed change mechanism of a tractor;

Fig. 2 is a view, partly in section, on the plane indicated by line11-11 in Fig. 1;

Fig. 3 is a sectional view on line IIIIII of Fig. 2; and

Fig. 4 is a sectional view on line IVIV of Fig. 2.

The reference character I designates a housing which encloses the masterclutch of the tractor, generally designated by the reference character2, the master clutch serving to selectively connect and disconnect theflywheel 3 of the tractor motor and a shaft 4 which for referencepurposes will be termed a power shaft. A speed change transmissionmechanism of conventional design Divided and this application August 3,

is generally designated by the reference character 5 and includes ahousing 6 and a pair of permanently meshing spur gears I and 8, the spurgear 1 being an upper gear and integrally formed with the power shaft 4at the rear end of the latter, and the spur gear 8 being a lower gearand journaled within the housing 6 on a countershaft 9. The spur gears land 8 are arranged in the usual manner closely adjacent to the forwardend wall of the transmission housing, and the interior space of thehousing, at the side of the spur gears I and 8 remote from the forwardend wall, extends from one side of a plane through the axes of shafts 4and 9 to the other and accommodates the ordinary variable speed gears.The housing 6 of the speed change transmission mechanism is bolted orotherwise rigidly secured to the clutch housing I, a vertical front wallI 8 of the transmission housing 6 abutting against a vertical rear wallI I of the clutch housing I, as shown in Fig. 1. The forward end of thepower shaft 4 is journaled in a pilot bearing in the flywheel 3, and therearward end of the power shaft 4 is joumaled in a ball bearing I2partly seated in the front wall I 8 of the transmission housing 6, andpartly seated in the rear wall II of the clutch housing I. The clutchhousing is mounted on the tractor between frame channels l3 and I4,mounting lugs I5 and I6 of the clutch housing being fitted into theframe channels, and bolts I'l holding the frame channels and mountinglugs together, as more fully explained in the mentioned originalapplication Serial No. 26,352, filed June 13, 1935.

A belt pulley shaft is indicated by the reference character I8 and isrotatably mounted in a sleeve I9 by means of a ball bearing 20 seated inthe sleeve I9 at one end thereof and by means of a roller bearing 2Iseated in the sleeve at the other end'thereof. The outer race of theroller bearing 2I abuts against a shoulder of the sleeve I9 and isretained by a snap ring 22, and the outer race of the ball bearing 20 issimilarly secured within the sleeve I9. The inner race of the ballbearing 20 is axially retained on the shaft I8 by a shoulder and a snapring 23, and the shaft is thus prevented from axial displacement withinthe sleeve I9. A bevel gear 24 is integrally formed with the shaft I8and meshes with a bevel gear 25 keyed to the power shaft 4, and a beltpulley 26 is secured to the outer end of the shaft I8 projecting fromthe sleeve I9. A suitable dust seal, not shown, may be mounted in theouter end of the sleeve I9 at the side of the roller bearing 2I facingthe hub of the belt pulley 26. The inner end of the sleeve I9 isslidingly fitted into a bore of an internal web 21 of the clutch housingI, the diameter of the bore corresponding within close limits to theoutside diameter of the portion of the sleeve 19 seated in the bore. Anintermediate portion of the sleeve I9 is slidingly fitted into a bore ofthe mounting lug I 6 of the clutch housing, the channel [4 having anaperture registering with the bore in the lug l6. An oil seal 28,preferably in the form of a cork ring, is retained in a counter bore ofthe lug l6 by the web of channel l4, and an internal flange 29 projectsinwardly from the sleeve l9. A portion of the sleeve intermediate theseats afforded by the bores in the web 21 and lug I6 is reduced indiameter and provided with a series of holes 30 and with an annulargroove 3|, the holes 30 being tapered to receive the tapered end of aset screw 32 which is screwed into a threaded hole of a wall portion ofthe clutch housing I. The holes 30, groove 3i and set screw 32 serve toretain the sleeve IS in the clutch housing I in a plurality of adjustedpositions, as is more fully disclosed in a copending application SerialNo. 94,016, filed August 3, 1936, Conrad E. Frudden, Pulley attachmentfor tractors.

The bevel gears 24 and 25 are enclosed in a gear compartment of theclutch housing I, the compartment providing an oil basin for the bevelgears 24 and 25 and being formed by an inclined bottom wall 33. avertical front wall 34, a vertical side wall 35, the web 21 and theupper part of the rear wall ll of the clutch housing. The top of thegear compartment is closed by a cover 36. It is desirable that the oillevel in the transmission housing 6 be kept below the variable speedshaft 31 of the speed change mechanism, approximately at the heightindicated in Fig. 1, and. on the other hand, it is desirable to maintainan oil level in the gear compartment of the clutch housing at a heightbelow the power shaft 4 and below the belt pulley shaft IS, the beltpulley shaft extending at right angles to the clutch shaft in ahorizontal plane through the axis of the latter. The desired oil levelin the gear compartment is indicated in Fig. l and is above the oillevel in the transmission housin 5. When the engine of the tractor isrunning it rotates the power shaft 4, provided that the clutch mechanism2 is engaged, and the lower gear 8 due to its mesh with the upper gear Iwill be rotated. The teeth of the lower gear 8. as they emerge from theoil in the transmission housing, are loaded with oil, the amount of oilclinging to the teeth of the gear being rather substantial because,according to usual practice, a relatively thick oil or heavy bodiedlubricant is used in the transmission housing. Only a small ortion ofthe oil which clings to the teeth of the lower gear 8 can pass the pointof mesh of the gears 8 and I, the remainder backing up ahead of thepoint of mesh and forming a spouting body of lubricant rising above thenormal oil level which is indicated in Fig. 1, the spouting action beingeffective not only in the plane of the intermeshing gears but alsocausing diffusion of the oil transversely to said plane. This fact isutilized to circulate some of the lubricant contained in thetransmission housing 3, through the gear compartment of the clutchhousing I and to maintain lubricant in said gear compartment at thelevel indicated in Fig. 1. In Fig. 2 the pitch circles of the gears Iand 8 are indicated in dash dotted lines, and the arrows in each circleindicate the directions in which the gears are rotated by the engine ofthe tractor. The rear wall H of the clutch housing has a hole 38 in it,and the front wall H] of the transmission housing has a similar hole 39in it concentric with the hole 38 in the rear wall of the clutchhousing, as shown in Figs. 2 and 4. The center of the hole 38 is solocated with respect to the pitch circles of the gear l and 8 that some01' the lubricant which builds up near the relatively approaching teethof the intermeshing gears, as mentioned above, is spouted through thehole 39 in the front wall of the transmission housing and through thehole 38 in the rear wall of the clutch housing into the gear compartmentof the latter. While some of the lubricant which builds up ahead of thepoint of mesh of the gears I and 8 is diffused transversely of the gearstowards the forward end wall of the transmission housing another portionof said lubricant is diffused transsversely of the gears in the oppositedirection. This latter portion of the lubricant circulates through thespace at the rear side of the gears I and 8 substantially withoutobstruction. It should be noted that the holes 38 and 39 are notdirectly below the axis of shaft 4 but positioned laterally of avertical longitudinal plane through the axis of shaft 4, and above thepitch circle of the lower gear 8 in proximity to the latter and also inproximity to the pitch circle of the upper gear I. At the point wherethe holes 38 and 39 are located, as shown in Fig. 2, the transversespouting of the lubricant is sufiiciently effective to transferlubricant from the transmission housing into the gear compartment of theclutch housing, and the oil passing through the holes 38 and 39 issubject to a pressure which would be suflicient to raise the oil in thegear compartment to a level considerably higher than that indicated inFig. 1. The counter spur gear 8 is freely exposed, at its circumferenceand at its side remote from the front wall ID, to the interior of thetransmission housing 6. In other words, the counter spur gear 3 has anannular portion freely exposed to the interior of the transmissionhousing 6 and, being thus exposed, the counter spur gear 8 is incapableof direct cooperation with the transmission housing in the manner of agear pump. Pressure upon the oil passing through the holes 39, 38 isproduced by the direct coaction of the gears I and 8 with the lubricant,which causes the mentioned diffusion or spouting of the lubricanttransversely of and in opposite directions from the plane of the gears Iand 8.

The oil which enters the gear compartment of the clutch housing Ithrough the holes 39, 33 is under appreciable pressure, as stated, andin order to prevent such oil from rising too high in the gearcompartment and keep it as closely as possible at the level indicated inFig. 1, an outlet hole 40 is drilled into the rear wall of the clutchhousing I near the bottom wall 33 of the gear compartment, as shown inFigs. 2 and 3, and a similar hole 4| concentric with the hole 40 isdrilled into the front wall 10 of the transmission housing 6. The inletholes 38 and 39 and the outlet holes 40 and 4| are so positioned andproportioned that a circulation of lubricant therethrough takes place atthe proper rate to maintain the oil level in the gear compartment,approximately at the height indicated in Fig. 1. As shown in Fig. 2, theoutlet hole 40 in the rear wall of the clutch housing is located at theside 5 of a vertical longitudinal plane through the shaft 4 where theteeth of the intermeshing gears I and 8 recede from each other, and asthere is no back pressure at this side of the gears within thetransmission housing the oil from the gear compartment will flow backinto the transmission housing through the outlet hole 40 and through thehole 4! in the front wall of the transmission housing. The internalflange 29 of the sleeve l9 obstructs the flow of oil through the lowerpart of the sleeve, and the oil level in the gear compartment maytherefore be kept close to the shaft I8; however, the oil level is keptlow enough to prevent overflow between the lower side of shaft l8 andthe flange 29, and consequent loss of oil through the roller bearing 2|.

The transfer of oil from the transmission housing into the gearcompartment by the pumping action of the gears I and 8 is independent ofvariations of the oil level in the transmission housing, within certainlimits. The normal loss of oil from the transmission housing, which isincident to the operation of the tractor, causes a lowering of the oillevel in the transmission housing, but it will not cause a lowering ofthe oil level in the gear compartment.

It should be noted that the lubricating system disclosed herein lendsitself in a very simple manner to use in connection with a change speedtransmission mechanism of standard construction and that it requires nochange in such standard transmission mechanism except that the holes- 39and 4| are drilled into the front wall of the transmission housing atthe proper places. It requires no parts in addition to those which arealready present in the standard transmission mechanism and it involvespractically no extra cost in the manufacture of the tractor.

It should be understood that it is not intended to limit the inventionto the exact details of construction herein shown and described, forvarious modifications within the-scope of the claims may occur topersons skilled in the art. For instance, the direction of rotation ofthe gears I and 8 could be reversed in which case the lubricant elevatedby the gear 8 would be diffused transversely at the left side of thepoint of mesh of the gears 1 and 8 with reference to Fig. 2, and insteadof entering the bevel gear compartment through the holes 38, 39, asdescribed hereinbefore, the lubricant would enter the bevel gearcompartment through the holes 40 and M and return into the transmissioncompartment through the holes 38 and 39. The holes 38 and 39 are locatedat a level below the power take-off shaft I8, and sufficient lubricantwould accumulate in the bevel gear compartment to keep the lower portionof the bevel gears 24 and 25 immersed therein. but due to the overflowthrough the holes 38, 39, the lubricant could not rise to such a heightthat it would overflow at the flange 29 in the sleeve l9.

It is claimed and desired to secure by Letters Patent:

1. In a lubricating system, a housing containing intermeshing upper andlower gears adjacent to a wall portion thereof and having an interiorspace, at the side of said gears remote from said wall portion,extending from one side of a plane through the axes of said gears to theother, a compartment communicating with said housing through an inletopening in said wall portion and through an outlet opening, and meansrequiring lubrication within said compartment including a positivelydriven rotatable element adapted to dip into lubricant accumulatingwithin said compartment, said inlet opening being offset from the pointof mesh of said gears towards the relatively approaching teeth thereof,whereby heavy bodied lubricant elevated by said lower gear and diffusedtransversely ahead of said point of mesh towards said wall portion willbe transferred from said housing into said compartment through saidinlet opening, while the portion of said lubricant diffused transverselyof said gears in the opposite direction will circulate through saidspace substantially without obstruction.

2. In a motor vehicle having a horizontally disposed power shaft and asupport therefor ineluding a vertical wall element, the combination of awalled structure associated with said support providing a gearcompartment around a portion of said power shaft at one side of saidwall element adapted to contain lubricant, a power takeoff shaftrotatably mounted on said support and projecting into said gearcompartment, means including a rotary element secured to said powershaft within said gear compartment for drivingly connecting said powershaft with said power takeoff shaft, a transmission housing adjacent tosaid wall element at the other side thereof adapted to containlubricant, a driving spur gear within said transmission housingnon-rotatably secured to said power shaft in axially fixed positionadjacent to said wall element, a counter spur gear within saidtransmission housing below said driving spur gear and in constant meshtherewith, said counter spur gear having an annular portion freelyexposed to the interior of said transmission housing, a variable speedshaft within said transmission housing, and means including saidpermanently meshing spur gears for selectively transmitting power atdifferent speed ratios from said power shaft to said variable speedshaft, said gear compartment communicating with the interior of saidtransmission housing through an opening in said wall element offset fromthe point of mesh of said spur gears towards the rela tively approachingteeth thereof and in proximity to said teeth, whereby heavybodiedlubricant elevated by. said counter spur gear and diffused transverselyahead of said point of mesh towards said wall element will betransferred from said transmission housing into said gear compartmentwhile the portion of said lubricant diffused transversely of said spurgears in the opposite direction will circulate substantially withoutobstruction within said transmission housing.

3. In a motor vehicle having a horizontally disposed power shaft and asupport therefor including a vertical wall element, the combination of awalled structure associated with said support providing a gearcompartment around a portion of said power shaft at one side of saidwall element adapted to contain lubricant, a sleeve mounted in a sideopening of said gear compartment in a horizontal position to extendtransversely of said power shaft, a power takeoif shaft extendingthrough said sleeve, antifriction bearings within said sleeve supportingsaid power takeoff shaft, a flange element within said sleeve arrangedto obstruct flow of lubricant through the lower part of said sleeve,cooperating bevel gears respectively secured to said power shaft andsaid power takeoff shaft within said gear compartment to transmitrotation of said power shaft to said power takeoff shaft, a transmissionhousing adjacent to said wall element at the other side thereof adaptedto contain lubricant, a driving spur gear within said transmissionhousing non-rotatably secured to said power shaft in axially fixedposition adjacent to said wall element, a counter spur gear within saidtransmission housing below said driving spur gear and in constant meshtherewith, said counter spur gear having an annular portion freelyexposed to the interior of said transmission housing, a variable speedshaft within said transmission housing, and means including saidpermanently meshing spur gears for selectively transmitting power atdiflerent speed ratios from said power shaft to said variable speedshaft, said gear compartment communicating with the interior of saidtransmission housing through an inlet opening in said wall elementofiset from the point of mesh of said spur gears towards the relativelyapproaching teeth thereof and in proximity to said teeth, whereby heavybodied lubricant elevated by said counter spur gear and difl'usedtransversely ahead 01 said point of mesh towards said wall element willbetransi'erred from said transmission housing into said gear compartmentwhile the portion of said lubricant diirused transversely of said spurgears in the opposite direction will circulate substantially withoutobstruction within said transmission housing, and said ear compartmentcommunieating with the interior of said transmission housing through anoutlet opening in said wall element arranged to prevent lubricantaccumulating within said gear compartment from overflowing at saidflange element.

WALTER F. STREHLOW.

